Testosterone in females: Mediator of adaptive traits, constraint on sexual dimorphism, or both?
(2005) In American Naturalist 166(4). p.85-98- Abstract
- When selection on males and females differs, the sexes may diverge in phenotype. Hormones serve as a proximate regulator of sex differences by mediating sex-biased trait expression. To integrate these perspectives, we consider how suites of traits mediated by the same hormone in both sexes might respond to selection. In male birds, plasma testosterone (T) varies seasonally and among species according to mating system. When elevated experimentally, it is known to enhance some components of fitness and to decrease others. We report that female T also varies seasonally and co-varies with male T. Female T is higher in relation to male T in sexually monomorphic species and is higher absolutely in females of species with socially monogamous... (More)
- When selection on males and females differs, the sexes may diverge in phenotype. Hormones serve as a proximate regulator of sex differences by mediating sex-biased trait expression. To integrate these perspectives, we consider how suites of traits mediated by the same hormone in both sexes might respond to selection. In male birds, plasma testosterone (T) varies seasonally and among species according to mating system. When elevated experimentally, it is known to enhance some components of fitness and to decrease others. We report that female T also varies seasonally and co-varies with male T. Female T is higher in relation to male T in sexually monomorphic species and is higher absolutely in females of species with socially monogamous mating systems, which suggests adaptation. We also consider the effect of experimentally elevated T on females and whether traits are sensitive to altered T. We hypothesize that sensitive traits could become subject to selection after a natural change in T and that traits with opposing fitness consequences in males and females could constrain dimorphism. Results from birds, including the dark-eyed junco (Junco hyemalis), reveal many sensitive traits, some of which appear costly and may help to account for observed levels of sexual dimorphism. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/218944
- author
- Ketterson, E D ; Nolan, V and Sandell, Maria LU
- organization
- publishing date
- 2005
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- hormonal, sex differences, hormonal pleiotropy, correlated responses, constraint, dark-eyed junco
- in
- American Naturalist
- volume
- 166
- issue
- 4
- pages
- 85 - 98
- publisher
- University of Chicago Press
- external identifiers
-
- wos:000232603500007
- scopus:26644474769
- ISSN
- 0003-0147
- DOI
- 10.1086/444602
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Animal Ecology (Closed 2011) (011012001)
- id
- 4a3ac266-5a14-4588-9979-dc6793b57e6f (old id 218944)
- date added to LUP
- 2016-04-01 12:15:51
- date last changed
- 2022-04-21 04:58:46
@article{4a3ac266-5a14-4588-9979-dc6793b57e6f, abstract = {{When selection on males and females differs, the sexes may diverge in phenotype. Hormones serve as a proximate regulator of sex differences by mediating sex-biased trait expression. To integrate these perspectives, we consider how suites of traits mediated by the same hormone in both sexes might respond to selection. In male birds, plasma testosterone (T) varies seasonally and among species according to mating system. When elevated experimentally, it is known to enhance some components of fitness and to decrease others. We report that female T also varies seasonally and co-varies with male T. Female T is higher in relation to male T in sexually monomorphic species and is higher absolutely in females of species with socially monogamous mating systems, which suggests adaptation. We also consider the effect of experimentally elevated T on females and whether traits are sensitive to altered T. We hypothesize that sensitive traits could become subject to selection after a natural change in T and that traits with opposing fitness consequences in males and females could constrain dimorphism. Results from birds, including the dark-eyed junco (Junco hyemalis), reveal many sensitive traits, some of which appear costly and may help to account for observed levels of sexual dimorphism.}}, author = {{Ketterson, E D and Nolan, V and Sandell, Maria}}, issn = {{0003-0147}}, keywords = {{hormonal; sex differences; hormonal pleiotropy; correlated responses; constraint; dark-eyed junco}}, language = {{eng}}, number = {{4}}, pages = {{85--98}}, publisher = {{University of Chicago Press}}, series = {{American Naturalist}}, title = {{Testosterone in females: Mediator of adaptive traits, constraint on sexual dimorphism, or both?}}, url = {{http://dx.doi.org/10.1086/444602}}, doi = {{10.1086/444602}}, volume = {{166}}, year = {{2005}}, }